What do you do if you have nut grass growing in your pool?

Question

Had an above ground pool put in and pool has been in operation for 10 days and I noticed grass growing thru liner.

Answer 1

I have heard of this before and was advised that if you
inject 'Round-up' weed killer with a syringe needle into the
plant then use a patch kit over the hole then you should be
Ok.

Answer 2

you should have put plastic sheet down first. You now probably have a water leak where the grass is comming through